Components and connections within integrated circuits (ICs) often generate electrical noise during use. ICs have to be designed so that the noise generated from a component or connection does not interfere with the performance of other components and connections within the same IC or other ICs in the system. An example of a noise generated by a component and connection is a ripple voltage. A ripple voltage is an alternating current (AC) component that adds to the direct current (DC) component of a voltage. One method of removing or reducing ripple voltage is with the use of bypass capacitors. Bypass capacitors are more effective as the equivalent series inductance (ESL) and equivalent series resistance (ESR) between the IC and its bypass capacitance is minimized.
As IC packages shrink to satisfy the desire for reduced size and weight, conventional chip bypass capacitors used to eliminate or reduce noise have been moved out of and/or off the host packages and onto the host printed wiring board (PWB). This results in longer path lengths between the IC and its bypass capacitance. The parasitic series resistance and inductance of the longer path length increases the ESL and ESR of the IC's bypass capacitance, making it less effective.
For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a method of providing effective bypass capacitance to an IC.